text: For most gases over a wide range of temperature and pressure,  is approximately constant. Therefore, it can be used to determine the thermal conductivity of gases at high temperatures, where it is difficult to measure experimentally due to the formation of convection currents.
  Typical values for  are:
  * 0.003 for molten potassium at 975 K
  * around 0.015 for mercury
  * 0.065 for molten lithium at 975 K
  * around 0.16–0.7 for mixtures of noble gases or noble gases with hydrogen
  * 0.63 for oxygen
  * around 0.71 for air and many other gases
  * 1.38 for gaseous ammonia
  * between 4 and 5 for R-12 refrigerant
  * around 7.56 for water (At 18 °C)
  * 13.4 and 7.2 for seawater (At 0 °C and 20 °C respectively)
  * 50 for n-butanol
  * between 100 and 40,000 for engine oil
  * 1000 for glycerol
  * 10,000 for polymer melts
  * around 1 for Earth's mantle.